1. Field of Invention
The present invention pertains to ligating instruments and, more particularly, to ligating instruments particularly useful in endoscopic operative procedures to ligate anatomical tissue and methods of ligating anatomical tissue in endoscopic operative procedures.
2. Discussion of the Prior Art
Closed, or endoscopic, surgery, also known as least-invasive surgery, has become extremely popular for use in conducting many various procedures such as, for example, laparoscopy (pelviscopy), gastroentroscopy, laryngobronchoscopy and arthroscopy. In endoscopic operative procedures, access to surgical sites in the body is gained through portals of minimal size formed in tissue of the body to allow instruments to be introduced at the surgical sites via the portals. Endoscopic surgery provides many benefits over open surgery, which typically requires skin incisions of substantial size, including minimal invasiveness and trauma, avoidance of complications due to surgery, greatly reduced wound healing times, patient discomfort and hospitalization and rehabilitation times and concomitant cost savings associated with shorter hospital stays and performing surgery without general anesthesia and in non-hospital or out-patient surgery sites. Ligating anatomical tissue is a time consuming and tedious part of both endoscopic and open operative procedures due to the difficulty involved in applying an occluding ligature in anatomical tubular or non-tubular tissue or organ structure as is desirable in occluding or tying organ and tissue structure in many various procedures. Ligating anatomical tissue is particularly difficult in endoscopic surgery due to the limited room for maneuverability at the surgical site and the complicated operative steps required; and, accordingly, the advantages of endoscopic surgery are sometimes outweighed by the disadvantages caused by the length of time required to perform endoscopic procedures where such time is significantly extended due to the time required for ligation. Because endoscopic surgery is greatly preferred over open surgery, much effort has been spent to develop techniques for facilitating tissue ligation. One technique involves the use of ligating devices such as, for example, the Endoloop.TM. manufactured by Ethicon, Inc. Such ligating devices typically include an elongate tubular member defining a lumen for passage therethrough of a length of ligature material, the ligature material having an end secured to a proximal end of the tubular member. A portion of the ligature material disposed externally of a distal end of the tubular member is formed as a ligature loop, the loop being made by passing the ligature material through a knot formed in an end of the ligature material externally of the tubular member distal end. In use, the tubular member distal end is introduced, typically via a portal sleeve, at a surgical site in the body through a portal of minimal size formed in tissue of the body, with the proximal end of the tubular member held and secured externally of the body. The ligature loop is positioned around tissue to be ligated within the body; and, once the tissue is properly positioned within the loop, the tubular member is broken or fractured to break off or separate the proximal end from the remainder thereof. The ligature material can then be pulled, via the broken off proximal end, through the lumen of the tubular member while the knot, which is larger than the lumen at the tubular member distal end, remains held externally of the distal end such that the loop is reduced or tightened around the tissue to form a ligature. Once the ligature is formed, a surgical instrument introduced at the surgical site from another portal is used to cut the ligature material away from the knot leaving the ligature in place. The ligating devices require use of both of the surgeon's hands, one hand to hold the tubular member externally of the body and the other to break off the proximal end and pull the ligature material therewith while the one hand continues to hold the tubular member. Forming ligatures in endoscopic operative procedures in accordance with the ligating devices is tedious and time consuming due to the number and complexity of the procedural steps involved.